Surveying instrument.



E. RGRAVBS.

SURVEYING INSTRUMENT.

' APPLICATION IILED AUG. 28, 1911.

Patented Aug. 20, 1912.

2 SHEETS-SHEET 1.

0-, WASHINGTON, D. c.

E. R. GRAVES.

SURVEYING INSTRUMENT.

APPLICATION FILED AUG. 28, 1911.

'2 SHEETS-SHEET 2.

w IIQWUFQI m v Patented Aug. 20, 1912.

coLuMmA PLANOGRAPH C0,, WASHINGTON n c EDWIN R. GRAVES, OF ST. LOUIS,MISSOURI.

SURVEYING INSTRUMENT.

Application filed August 28, 1911.

in surveying instruments.

One object of the invention is to provide a surveying instrument havingan improved construction and arrangement of supporting mechanism for thesighting tube whereby the latter may be readily adjusted for sight- 1ing in any direction.

Another ob ect 1s to provlde a surveying or leveling instrument whichwill be simple,

strong, durable and inexpensive in construction, efficient and reliablein operation and well adapted to the purpose for which it is designed.

With these and other objects in view, the invention consists of certainnovel features of construction and the combination and arrangement ofparts as will be more fully described and claimed.

In the accompanying drawings: Figure 1 is a side view of my improvedsurveying instrument; Fig. 2 is a central vertical cross sectional viewon the line 2-2 of Fig. 1; Fig. 3 is a central vertical longitudinal section; Fig. 4 is a horizontal sectional view on the line H of Fig. 3;Fig. 5 is a vertical cross section through the sighting tube on the line55 of Fig. 3; Fig. 6 is a similar view on the line 6-6 of Fig. 3; Fig. 7is a detail perspective view of one of the ferrules employed in the endsof the sight ing tube for securing the lens and sighting disk in place;Fig. 8 is a detail view of one of the spacing blocks employed betweenthe level and the sighting tube.

In the embodiment of the invention, I provide a socket 1 having on itslower end an annular radially projecting base plate 2 which is adaptedto be screwed or otherwise secured to the head 3 of a tripod or to anyother suitable support. The socket 1 is provided with tapered oroutwardly flared inner side walls 4 as shown and in the sides of thesocket at suitable distances apart Specification of Letters Patent.

Patented Au 20, 1912.

Serial No. 646,432.

gaged post supporting and adjusting screws 6 the inner ends of which areadapted to engage and support av tube and spirit level supporting post 7which is engaged with the tapered recess of the socket 1 and has its endrounded to fit the rounded inner end of the socket whereby said post maybe readily adjusted to the desired angle by the screws 6. V v

Adapted to be revolubly engaged with the upper end of the post 7 is atube supporting frame 8 comprising side plates 9 the upper portions of"which are provided with curved lugs 10 adapted to fit around the lowerside of the sighting tube 11, said tube being brazed or otherwiserigidly secured to the lugs. In the side plates 9 between the lugs 10are formed openings the purpose of which will hereinafter appear. Theside plates 9 are connected together at their lower edges by an'integralbottom plate on which is formed a centrally disposed cylindrical socket12 which is adapted to loosely engage the upper end of the post 7 asshown whereby the tube 11 is revolubly supported.

Arranged in the frame 8 between the side plates 9 is a longitudinallydisposed spirit level 13, said level being held in the frame 8 inparallel relation to the tube 11 by clamping screws 14 arranged in thebottom plate of the frame 8 and adapted to be screwed up into engagementwith the lower side of the spirit level 13 whereby the latter issecurely clamped against spacing blocks 15 arranged in the frame 8between the side plates 9. The blocks 15 have a curved upper surface asshown in Fig. 8 adapted to fit the adjacent curved side of the sightingtube and have flat lower surfaces adapted to fit the flat upper surfacesof the spirit level ends. By thus arranging and securing the spiritlevel the latter may be readily removed for any purpose and quicklyreplaced and fastened in position.

The ends of the sighting tube 11 are enlarged and threaded interiorlyfor a suit-able distance as shown to provide seats 16 and 17. With theseat 16 in one end of the tube 11 is adapted to be engaged a glass disk18 while with the seat 17 is engaged a sighting disk 19 having formedtherein a centrally disposed perforation or sight-ing hole 20. The disk18 and sighting disk 19 are held in place in engagement with theirrespective seats by ferrules 21,- said ferrules having reducedexteriorly threaded inner ends and having the surface of their outerends milled or checkered whereby the ferrules may be readily screwedinto and out of the exteriorly threaded ends of the sighting tube. Themilled surfaces of the outer ends of the ferrules are perfectly flushwith the outer surface of the tube as shown.

By providing a socket and a supporting post such as herein shown anddescribed it will be seen that the sighting tube of the instrument maybe adjusted to any desired angle of inclination within certain limitsand in any direction, in which position the same may be securelyfastened by the screws 6. The pivotal engagement of the tube supportingframe with the post 7 will aermit the tube to be readily turned to thedesired position or in the desired direction. By providing the spiritlevel 13 and arranging the same as herein shown and described theposition of the tube will be indicated. The glass of the level may bereadily observed through the recesses formed in the side plates 9 of theframe between the lugs 10 as hereinbefore described.

The disk 18 is provided with any suitable center indicating marks and ishere shown as being provided with lines 22 which cross at right anglesto each other in the center of the disk.

From the foregoing description taken in connection with the accompanyingdrawings, the construction and operation of the invention will bereadilyunderstood without requiring a more extended explanation.

Various changes in the form, proportion and the minor details ofconstruction may I be resorted to without departing from the principleor sacrificing any of the advantages of the invention as claimed.

Having thus described my invention, what I claim is:

1. A surveying instrument, comprising a socket having a tapered recess,"means to secure said socket to a suitable support, a supporting postloosely arranged in said socket, a series of radially disposed post insaid socket and adapted to engage said post whereby the same is adjustedand held in position, a tube supporting frame revolubly mounted on saidpost, a sighting tube secured to said frame, and a spirit level.

arranged in the frame whereby the position of the latter and the tube 1sndlcated.

2. In a surveylng instrument, a socket adjusting and supporting screwsarranged I having a tapered recess, means to attach sighting diskarranged in the other end of the tube, said disk having formed therein acentrally disposed sighting aperture, ferrules adapted to be screwedinto the ends of said tube'whereby said disks are removably heldlnplace, a splrit level arranged in said frame, spacing blocksarranged'between said level and the adjacent side of the tube, andclamping screws arranged in' said frame and adapted to be screwed intoengagement with said spirit level whereby the latter is clamped againstsaid spacing blocks and thereby removably held in position. r v v V Intestimony whereof I have hereunto set my hand in presence of twosubscribing witnesses. V

EDI/VIN R. GRAVES. Witnesses: j

DANIEL W. YORKE, HENRY L. LINS.

copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

